超声非线性效应表征的动态小波指纹分析方法  

Identification of nonlinear ultrasonic effects using method of dynamic wavelet fingerprint

作　　者：焦敬品[1,2] 吕洪涛[1] 孟祥吉[1] 吴斌[1,2] 何存富[1,2] 

机构地区：[1]北京工业大学机械工程与应用电子技术学院,北京100124 [2]北京工业大学北京市精密测控技术与仪器工程技术研究中心,北京100124

出　　处：《声学学报》2017年第5期560-570,共11页Acta Acustica

基　　金：国家自然科学基金项目(11572010;11272017);国家重点研发计划项目(2016YFF0203002)资助

摘　　要：针对结构早期损伤超声非线性检测中损伤表征问题,发展了一种基于动态小波指纹的超声信号分析方法,从超声信号的动态小波指纹分布中提取出一种可用于结构早期损伤表征的超声非线性特征参数。研究了小波基函数及分析尺度对超声非线性效应提取效果的影响,优选出对结构早期损伤敏感的小波基函数以及尺度范围。将提出的动态小波指纹分析方法应用于二次谐波及混频非线性超声检测信号分析,结果表明,动态小波指纹分析方法可有效提取出检测信号中的二次谐波及混频分量,基于小波指纹分布的非线性特征参数可用于板结构中微裂纹的定量表征.本文研究工作为结构早期损伤超声非线性检测中的弱非线性效应提取作了有益探索。Toward the characterization of early stage damage of structures by nonlinear ultrasonic testing technology, a dynamic wavelet fingerprint （DWFP） analysis method was developed for nonlinear ultrasonic signal analyzing, and nonlinear characterization parameter of early damage based on DWFP distribution was proposed as well. Meanwhile the influence of different wavelet basis functions and scale extents on nonlinear ultrasonic effects extraction is investigated, and the optimal wavelet basis functions and scale extents sensitive to early stage damage are obtained. After that, DWFT analysis method was applied to harmonic and frequency-mixing nonlinear ultrasonic test signals analysis. It has been shown that DWFT analysis method can effectively extract the harmonic and frequency-mixing components embedded in testing signals, and nonlinear characterization parameter based on DWFP distribution is capable of quantifying characterization of micro-crack in plate structures. Useful exploration is done for nonlinear ultrasonic testing signal analysis.

关 键 词：弱非线性效应 小波基函数 指纹分析 超声检测 定量表征 声信号分析 早期损伤 非线性检测 

分 类 号：TB559[理学—物理] TP391.41[理学—声学]